This invention is directed generally to the article handling arts and more particularly to a novel and improved article hold up apparatus for maintaining a group of articles in a facewise nested condition as the articles are transported along an elongate lane.
While the apparatus of the invention may find utility in other applications, the disclosure will be facilitated by particular reference to the handling of can ends during their fabrication and/or subsequent use as closures for can bodies. In the manufacture and filling of containers such as beverage cans or the like, a great number of can end parts are required. Modern fabrication and filling operations require that can ends be provided at a high rate of speed in a more or less continuous process. A number of individual processing steps are utilized in fabricating the can ends prior to their eventual use as closures.
In this regard, the can ends are often packaged and shipped to the final end user, although in some instances, the fabricator may also be the end user. The fabrication of can ends requires a number of steps including initial stamping or formation of the ends from suitable aluminum or other material or blanks, the formulation of suitable scoring for a tear away top portion and application of a graspable tab, ring or the like, as well as the adding of suitable liner materials as may be required for various applications. Such liners may be required to effect "repair" or assure the integrity of the end after the scoring and tab applying operation, or may be required as a condition of packaging for various products.
In the can end fabricating operation, can ends are generally fed from one station to the next in a more or less continuous flow in an endwise or facewise stacked or nested condition. Where can ends are to be packaged for shipment to a final user and unpackaged by the final user, the ends are generally provided in stacks or "sticks" as they are called in the art, of a predetermined number or length of ends in facewise nested condition.
However, during the handling of ends between one station and another in a fabricating or filling process, many instances arise in which a leading end of a flow or stream of can ends must be introduced to a portion of the processing apparatus. That is, a discontinuity occurs in the otherwise continuous flow of can ends. When such a discontinuity occurs, some means must be provided to assure that leading ones of the ends in the incoming stream are maintained in an upright coaxial or nested condition with the following ends. In such apparatus, the ends are often fed into an elongate lane which essentially comprises a pair of support rails which are spaced to engage spaced apart points about the bottom part of the circumference of the ends. These support rails are generally below center with respect to the circumferences of the ends. Sometimes it is necessary to provide for access by other handling equipment for gripping or otherwise handling the ends about their peripheries in an over-center fashion. For example, such apparatus, generally referred to as "pick-and-place" devices are used in applications such as are shown for example in prior U.S. Pat. Nos. 4,979,870 and 5,119,617, both of which are commonly owned with this application.
While the apparatus of the present application may find other uses, reference is particularly directed to the automatic tray loading, unloading and storage system, and to the multi-lane infeed counter/bagger, shown respectively in the above-referenced two U.S. patents. In both of these apparatus, can ends must be introduced into elongate lanes as a preliminary to various handling steps, such that it is necessary to assure that the leading ends of a continuous flow of can ends being introduced into such lanes are maintained in an upright nested condition. Generally speaking, the prior art has utilized hold up means or apparatus in the form of one or more pairs of elongate flexible or resilient strips of rubber or rubber-like material, as shown for example in FIG. 2 of U.S. Pat. No. 4,742,669, which is also commonly owned herewith. In this regard, the present invention may also find application in the can end counting system, and particularly in the application shown in FIG. 2, of the aforesaid U.S. Pat. No. 4,742,669. In each of the above-referenced three U.S. patents, there occur instances in which the can ends are separated from a more or less continuous incoming flow into individual groups or sticks of a predetermined number or length. Therefore, a discontinuity occurs each time one of these groups or sticks is separated out or removed from the incoming flow and a new group or stick is to be formed from the incoming flow of ends.
Such rubber hold up strips generally run the entire length of the lane, until such point as some further handling equipment or hold up mechanism is encountered by the advancing ends. While this arrangement had found widespread acceptance, there remains room for improvement. For example, the hold up strips are subject to wear over a long period of use and must therefore be periodically inspected and replaced. Also, various coatings, lubricants or other materials which may be present, either in connection with coatings on the ends themselves or otherwise, tend to build up on these elongate strips over a period of time, also necessitating periodic inspection and cleaning or replacement thereof. One aim of the present invention is to eliminate the need for such periodic inspection and replacement of hold up strips, while yet providing a hold up or support function, that is, for maintaining the can ends in a facewise nested condition as they are introduced into an elongate lane.